Hydrophobic-action-driven removal of six organophosphorus pesticides from tea infusion by modified carbonized bacterial cellulose

Abstract

The abuse of organophosphorus pesticides (OPPs) in tea planting makes it easy to transfer from tea into its infusion, bringing potential health risks to consumers. Thus, it is essential to adopt reliable techniques to remove OPPs from tea infusion. In this study, three treatment methods were used to modify carbonized bacterial cellulose (CBC) to improve its adsorption performance. Among them, CBC treated by hydrazine hydrate (N-CBC) had the best adsorption effect, whose removal rate for dicrotophos is 13 times that of CBC. The in-depth study of adsorption mechanism proved that hydrophobic interaction dominated the adsorption of OPPs onto N-CBC. The pseudo-second-order kinetic model and Langmuir isotherm model were more suitable to describe the process. Additionally, there were no significant changes in tea infusion quality after N-CBC treatment. This work clarifies that N-CBC benefitted from simple preparation method, excellent adsorption performance and unique adsorption mechanism has potential applications in tea infusion.

Keywords: Adsorption; Hydrophobic interaction; Modified carbonized bacterial cellulose; Organophosphorus pesticides; Tea infusion.